Scientific Name
Juncus balticus Willd. (Synonyms: Juncus arcticus ssp. littoralis)
Common Name(s)
Baltic rush, wire rush, wiregrass
Tribe / Family Name
Juncaceae
Flowering Period
June to August
Symbol
JUBA
Description
Baltic rush is a cool-season, native perennial grass-like plant that is produced either singly or in dense clumps from extensive creeping black rhizomes; reproduction occurs from seeds and rhizomes. Culms range from 30–100 cm in height with an erect and wiry growth habit; stems are round, smooth, dark green, and pithy inside. Inflorescences contain cymose clusters with usually 10–50 or more flowers appearing laterally on the stem. Involucral bracts are up to 20 cm long, round to somewhat flattened, erect, sharp-pointed, and appearing as a continuation of the stem. Flowers contain 6 tepals that are 3–6 mm long, lanceolate, acute to ovate, hyaline-margined, subequal, and greenish to dark brown; the 6 stamens have anthers that are 3–5 times longer than the filaments; flowers with prophylls. Stigmas 3. Fruits are a capsule, ovoid with an apiculate apex, and shorter to longer than the tepals. Leaves are cylindrical, erect, comprised mainly of basil sheaths, crowded near the base of the plant, and brown to reddish-brown.
General Info
Besides its nitrogen fixation and slope stabilization capabilities, this type of grass-like plant can be found in wet meadows, ponds, ditches, seeps, and lake and stream marshes; often associated with alkaline sites.
Similar Species
Baltic rush can look similar to other rushes, such as common rush (Juncus effusus) and thread rush (Juncus filiformis). Baltic rush usually have more dispersed stems while common rush has tufted stems arising from short rhizomes and anthers that are equal to or shorter than the filaments. Thread rush is shorter in height (5–40 cm) with tufted stems. Its stems and rhizomes are smaller in diameter compared to Baltic rush. Baltic rush and common rush also feature an arrangement of robust rhizomes, but all three species have leaves that are reduced to bladeless sheaths.
Picture of growth habit.
Inflorescences contain cymose clusters with 10-50 flowers appearing laterally on the stem.
Close-up picture of perfect flower with six tepals, six stamens, and three stigmas.
Cloe-up picture of rhizomes and roots.
Illustration of baltic rush. USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913. <i>An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols</i>. Charles Scribner's Sons, New York. Vol. 1: 468.